Chang Gung Forum: An Exemplary Strategy for Implementing a Multidisciplinary Network of Experts in Craniofacial Anomalies.

INTRODUCTION: The Chang Gung Forum has been dedicated to the care of craniofacial anomalies since 2000. This annual continuing medical education program focuses on orofacial cleft and surgery-first orthognathic surgery by providing up-to-date information and management guidelines. This study explored how the Chang Gung Forum has influenced medical perspectives, decisions, and practices in a multidisciplinary craniofacial team. METHODS: Between 2000 and 2022, 20 Chang Gung Forums have been held. A questionnaire was distributed among 170 attendees who had participated in the forum more than once. The questionnaire collected information on the participants' experiences and levels of satisfaction with the educational program and whether or how it had influenced their clinical practice. RESULTS: Valid responses from 86 attendees (response rate, 50.6%) who had participated more than once were collected and analyzed. The overall satisfaction rate of the Chang Gung Forum based on the respondents' most recent visits was 4.28 ± 0.63 out of 5. Of the respondents, 90.9% acknowledged changes in their clinical practice, with modifications in surgery plans and decisions being the most notable (48.5%). In addition, comprehension increased throughout years of attending the annual forum (P < 0.001). CONCLUSION: The Chang Gung Forum has contributed markedly to the community of congenital craniofacial anomalies. The program will continue providing updated information and influencing the clinical decision-making of health care professionals.

Structures of 1:1 and 2:1 complexes of BMVC and MYC promoter G-quadruplex reveal a mechanism of ligand conformation adjustment for G4-recognition.

BMVC is the first fluorescent probe designed to detect G-quadruplexes (G4s) in vivo. The MYC oncogene promoter forms a G4 (MycG4) which acts as a transcription silencer. Here, we report the high-affinity and specific binding of BMVC to MycG4 with unusual slow-exchange rates on the NMR timescale. We also show that BMVC represses MYC in cancer cells. We determined the solution structures of the 1:1 and 2:1 BMVC-MycG4 complexes. BMVC first binds the 5'-end of MycG4 to form a 1:1 complex with a well-defined structure. At higher ratio, BMVC also binds the 3'-end to form a second complex. In both complexes, the crescent-shaped BMVC recruits a flanking DNA residue to form a BMVC-base plane stacking over the external G-tetrad. Remarkably, BMVC adjusts its conformation to a contracted form to match the G-tetrad for an optimal stacking interaction. This is the first structural example showing the importance of ligand conformational adjustment in G4 recognition. BMVC binds the more accessible 5'-end with higher affinity, whereas sequence specificity is present at the weaker-binding 3'-site. Our structures provide insights into specific recognition of MycG4 by BMVC and useful information for design of G4-targeted anticancer drugs and fluorescent probes.

Impact of the Different Types of Le Fort I Maxillary Surgical Movement on Nasal Width Changes: A Photogrammetric Analysis.

BACKGROUND: Le Fort I maxillary movements affect nasal width, but nasal width changes with specific movement types have not been formally addressed to date. OBJECTIVES: The purpose of this study was to analyze and compare the changes in nasal width with different maxillary movements. METHODS: A retrospective study was performed among consecutive patients who underwent bimaxillary orthognathic surgery (n = 138) and who were grouped based on the type of maxillary movement (ie, maxillary advancement with intrusion [MAI], maxillary advancement with extrusion [MAE], and maxillary setback with intrusion [MSI]). Preoperative and 12-month postoperative nasal widths were analyzed photogrammetrically by 2 blinded evaluators. RESULTS: Maxillary advancement with intrusion and MAE presented a significantly (P < 0.05) higher alar base widening than MSI did, with no significant (P > 0.05) differences between MAI and MAE. Maxillary advancement movements (MAI and MAE) showed significantly (P < 0.05) higher alar base widening than maxillary setback movement (MSI). However, no significant (P > 0.05) difference was observed between maxillary intrusion (MAI and MSI) and maxillary extrusion (MAE) movements. CONCLUSIONS: This study shows that the nasal width varies distinctly depending on the type of Le Fort I maxillary surgical movement.

Skeletofacial Reconstruction for Cleft-Related Deformities: Four Decades of Evolving Cleft Care.

Skeletofacial reconstruction in skeletally mature patients with cleft lip/palate can be challenging because of multifaceted condition-specific anatomical features in addition to several repercussions from surgical intervention during the growing period. This surgical report presents the history and evolving philosophy of cleft-skeletofacial reconstruction at the Chang Gung Craniofacial Center, a referral center for cleft care in Taiwan. The maximization of satisfactory function and the appearance outcome-burden ratio have been the fundamental aims for this team to develop and upgrade cleft-skeletofacial reconstruction over the past 4 decades, with more than 10,000 mature patients treated. The study highlights key lessons learned in outcome-based and patient-oriented changes over time until the current approach, which focuses on patient-centered care with a comprehensive, multidisciplinary, and team-based model. Substantial advances in surgical, orthodontic, anesthetic, and computer imaging aspects have contributed to improving and optimizing the correction of a broad spectrum of facial and occlusal deformities while ensuring safety, predictability, efficiency, and stability in outcomes. Understanding the development and refinement of cleft-skeletofacial reconstruction over the time and transferring these time-tested and scientifically validated protocols and principles to clinical practice may serve as a reliable foundation to continue the advancement and enhancement of the delivery of surgical cleft care worldwide.

History and Evolution of Orthognathic Surgery at Chang Gung Craniofacial Center: Lessons Learned From 35-Year Experience.

BACKGROUND: Modern orthognathic surgery (OGS) was established on the basis of contributions from multidisciplinary centers worldwide. This study reports the history and evolution of OGS at the Chang Gung Craniofacial Center (CGCC) and identifies the lessons learned from 35 years of experience. METHODS: The total number of OGS procedures managed by the CGCC multidisciplinary team between 1981 and 2016 was determined. The database of the senior author (Y.-R.C.) was reviewed for consecutive OGS procedures performed between 2003 and 2016. A literature review was also performed to retrieve the contributions from the total CGCC team. RESULTS: The 35 years of experience at a single center and 13-year experience of a single surgeon corresponded to 8073 and 2883 OGS procedures, respectively. Moreover, 53 peer-reviewed articles were reviewed. Teamwork (plastic surgeons, orthodontists, and anesthetists) ensured an optimal balance between occlusion functional and facial aesthetic outcomes, with patient safety ensured and a minimum of OGS-related complications. Progression from the conventional orthodontics-first approach to the surgery-first OGS approach decreased the overall treatment time. Transition from 1-jaw to 2-jaw surgery enabled more consistent aesthetic outcomes to be achieved. Conversion from the 2-splint to the single-splint technique enabled development of a more precise tridimensional simulation plan and surgical execution, including in challenging scenarios such as malocclusion associated with facial asymmetry. Clockwise pitch rotation of the maxillomandibular complex has been designed for facial aesthetic purposes in class III malocclusion, whereas counterclockwise pitch rotation of the maxillomandibular complex improves airway function in those with sleep apnea. CONCLUSIONS: The lessons learned from experience and outcome-based articles reveal that OGS has successfully evolved at the CGCC, with a balance being achieved between functional and aesthetic outcomes and effective decreases in the burden of care (ie, morbidity, complications, and treatment time).

Ligand Selectivity in the Recognition of Protoberberine Alkaloids by Hybrid-2 Human Telomeric G-Quadruplex: Binding Free Energy Calculation, Fluorescence Binding, and NMR Experiments.

The human telomeric G-quadruplex (G4) is an attractive target for developing anticancer drugs. Natural products protoberberine alkaloids are known to bind human telomeric G4 and inhibit telomerase. Among several structurally similar protoberberine alkaloids, epiberberine (EPI) shows the greatest specificity in recognizing the human telomeric G4 over duplex DNA and other G4s. Recently, NMR study revealed that EPI recognizes specifically the hybrid-2 form human telomeric G4 by inducing large rearrangements in the 5'-flanking segment and loop regions to form a highly extensive four-layered binding pocket. Using the NMR structure of the EPI-human telomeric G4 complex, here we perform molecular dynamics free energy calculations to elucidate the ligand selectivity in the recognition of protoberberines by the human telomeric G4. The MM-PB(GB)SA (molecular mechanics-Poisson Boltzmann/Generalized Born) Surface Area) binding free energies calculated using the Amber force fields bsc0 and OL15 correlate well with the NMR titration and binding affinity measurements, with both calculations correctly identifying the EPI as the strongest binder to the hybrid-2 telomeric G4 wtTel26. The results demonstrated that accounting for the conformational flexibility of the DNA-ligand complexes is crucially important for explaining the ligand selectivity of the human telomeric G4. While the MD-simulated (molecular dynamics) structures of the G-quadruplex-alkaloid complexes help rationalize why the EPI-G4 interactions are optimal compared with the other protoberberines, structural deviations from the NMR structure near the binding site are observed in the MD simulations. We have also performed binding free energy calculation using the more rigorous double decoupling method (DDM); however, the results correlate less well with the experimental trend, likely due to the difficulty of adequately sampling the very large conformational reorganization in the G4 induced by the protoberberine binding.

Molecular Recognition of the Hybrid-2 Human Telomeric G-Quadruplex by Epiberberine: Insights into Conversion of Telomeric G-Quadruplex Structures.

Human telomeres can form DNA G-quadruplex (G4), an attractive target for anticancer drugs. Human telomeric G4s bear inherent structure polymorphism, challenging for understanding specific recognition by ligands or proteins. Protoberberines are medicinal natural-products known to stabilize telomeric G4s and inhibit telomerase. Here we report epiberberine (EPI) specifically recognizes the hybrid-2 telomeric G4 predominant in physiologically relevant K+ solution and converts other telomeric G4 forms to hybrid-2, the first such example reported. Our NMR structure in K+ solution shows EPI binding induces extensive rearrangement of the previously disordered 5'-flanking and loop segments to form an unprecedented four-layer binding pocket specific to the hybrid-2 telomeric G4; EPI recruits the (-1) adenine to form a "quasi-triad" intercalated between the external tetrad and a T:T:A triad, capped by a T:T base pair. Our study provides structural basis for small-molecule drug design targeting the human telomeric G4.

Structurally Diverse Alkaloids from the Seeds of Peganum harmala.

Investigation of the alkaloids from Peganum harmala seeds yielded two pairs of unique racemic pyrroloindole alkaloids, (±)-peganines A-B (1-2); two rare thiazole derivatives, peganumals A-B (3-4); six new ß-carboline alkaloids, pegaharmines F-K (5-10); and 12 known analogues. Their structures, including stereochemistry, were elucidated through spectroscopic analyses, quantum chemistry calculations, and single-crystal X-ray diffraction. Notably, the incorporation of pyrrole and indole moieties in peganines A-B, thiazole fragments in peganumals A-B, and a C-1 α,ß-unsaturated ester motif in pegaharmine F (5) are all rare, and their presence in the genus Peganum were demonstrated for the first time. All isolates were tested for antiproliferative activities against the HL-60, PC-3, and SGC-7901 cancer cell lines, and compounds 9, 11, 12, and 13 exhibited moderate cytotoxicity against HL-60 cancer cell lines with IC50 values in the range of 4.36-9.25 µM.

Solution structure of a 2:1 complex of anticancer drug XR5944 with TFF1 estrogen response element: insights into DNA recognition by a bis-intercalator.

XR5944, a deoxyribonucleic acid (DNA) bis-intercalator with potent anticancer activity, can bind the estrogen response element (ERE) sequence to inhibit estrogen receptor-α activities. This novel mechanism of action may be useful for overcoming drug resistance to currently available antiestrogen treatments, all of which target the hormone-receptor complex. Here we report the nuclear magnetic resonance solution structure of the 2:1 complex of XR5944 with the naturally occurring TFF1-ERE, which exhibits important and unexpected features. In both drug-DNA complexes, XR5944 binds strongly at one intercalation site but weakly at the second site. The sites of intercalation within a native promoter sequence appear to be context and sequence dependent. The binding of one drug molecule influences the binding site of the second. Our structures underscore the fact that the DNA binding of a bis-intercalator is directional and different from the simple addition of two single intercalation sites. Our study suggests that improved XR5944 bis-intercalators targeting ERE may be designed through optimization of aminoalkyl linker and intercalation moieties at the weak binding sites.

Selective lighting up of epiberberine alkaloid fluorescence by fluorophore-switching aptamer and stoichiometric targeting of human telomeric DNA G-quadruplex multimer.

Aptamers, that exist naturally in living cells as functional elements and can switch nonfluorescent natural targets to fluorophores, are very useful in developing highly sensitive and selective biosensors and screening functional agents. This work demonstrates that human telomeric G-quadruplex (HTG) can serve as a potential fluorophore-switching aptamer (FSA) to target a natural isoquinoline alkaloid. We found that, among the G-quadruplexes studied here and the various structurally similar alkaloids including epiberberine (EPI), berberine (BER), palmatine (PAL), jatrorrhizine (JAT), coptisine (COP), worenine (WOR), sanguinarine (SAN), chelerythrine (CHE), and nitidine (NIT), only the HTG DNA, especially with a 5'-TA-3' residue at the 5' end of the G-quadruplex tetrad (5'-TAG3(TTAG3)3-3', TA[Q]) as the minimal sequence, is the most efficient FSA to selectively light up the EPI fluorescence. Compared to the 5' end flanking sequences, the 3' end flanking sequences of the tetrad contribute significantly less to the recognition of EPI. The binding affinity of EPI to TA[Q] (K(d) = 37 nM) is at least 20 times tighter than those of the other alkaloids. The steady-state absorption, steady-state/time-resolved fluorescence, and NMR studies demonstrate that EPI most likely interact with the 5' end flanking sequence substructure beyond the core [Q] and the G-quadruplex tetrad in a much more specific manner than the other alkaloids. The highly selective and tight binding of EPI with the FSA and significantly enhanced fluorescence suggest the potential development of a selective EPI sensor (detection limit of 10 nM). More importantly, EPI, as the brightest FSA emitter among the alkaloids, can also serve as an efficient conformation probe for HTG DNA and discriminate the DNA G-quadruplex from the RNA counterpart. Furthermore, EPI can bind stoichiometrically to each G-quadruplex unit of long HTG DNA multimer with the most significant fluorescence enhancement, which has not been achieved by the previously reported probes. Our work suggests the potential use of EPI as a bioimaging probe and a therapeutic DNA binder.

The major G-quadruplex formed in the human BCL-2 proximal promoter adopts a parallel structure with a 13-nt loop in K+ solution.

The human BCL-2 gene contains a 39-bp GC-rich region upstream of the P1 promoter that has been shown to be critically involved in the regulation of BCL-2 gene expression. Inhibition of BCL-2 expression can decrease cellular proliferation and enhance the efficacy of chemotherapy. Here we report the major G-quadruplex formed in the Pu39 G-rich strand in this BCL-2 promoter region. The 1245G4 quadruplex adopts a parallel structure with one 13-nt and two 1-nt chain-reversal loops. The 1245G4 quadruplex involves four nonsuccessive G-runs, I, II, IV, V, unlike the previously reported bcl2 MidG4 quadruplex formed on the central four G-runs. The parallel 1245G4 quadruplex with the 13-nt loop, unexpectedly, appears to be more stable than the mixed parallel/antiparallel MidG4. Parallel-stranded structures with two 1-nt loops and one variable-length middle loop are found to be prevalent in the promoter G-quadruplexes; the variable middle loop is suggested to determine the specific overall structure and potential ligand recognition site. A limit of 7 nt in loop length is used in all quadruplex-predicting software. Thus, the formation and high stability of the 1245G4 quadruplex with a 13-nt loop is significant. The presence of two distinct interchangeable G-quadruplexes in the overlapping region of the BCL-2 promoter is intriguing, suggesting a novel mechanism for gene transcriptional regulation and ligand modulation.

Cancer risk with topical calcineurin inhibitors, pimecrolimus and tacrolimus, for atopic dermatitis: a systematic review and meta-analysis.

BACKGROUND: Atopic dermatitis is a prevalent condition in children and can be effectively managed with medications such as topical calcineurin inhibitors (pimecrolimus or tacrolimus). A key unresolved safety concern is whether use of topical calcineurin inhibitors is associated with cancer. We systematically reviewed the risk of cancer in patients with atopic dermatitis exposed to topical calcineurin inhibitors. METHODS: As part of the 2022 American Academy of Allergy, Asthma and Immunology and American College of Allergy, Asthma and Immunology Joint Task Force on Practice Parameters atopic dermatitis guidelines, we searched MEDLINE, Embase, the Latin American and Caribbean Health Sciences Literature database, the Índice Bibliográfico Espanhol de Ciências da Saúde database, the Global Resource of Eczema Trials database, WHO's International Clinical Trials Registry Platform, the US Food and Drug Administration database, the European Medicines Agency database, company registers, and relevant citations from inception to June 6, 2022. We included randomised controlled trials and comparative and non-comparative non-randomised studies in any language addressing cancer risk in patients with atopic dermatitis using topical calcineurin inhibitors. We excluded split-body studies and studies with less than 3 weeks of follow-up. Paired reviewers independently screened records, extracted data, and assessed risk of bias in duplicate. We used Bayesian models to estimate the probability for cancer due to topical calcineurin inhibitor exposure and the GRADE approach to determine the certainty of the evidence. Patients, advocacy groups, and care providers set a priori thresholds of important effects. This study is registered with Open Science Framework, https://osf.io/v4bfc. FINDINGS: We identified and analysed 110 unique studies (52 randomised controlled trials and 69 non-randomised studies [11 were non-randomised study extensions of randomised controlled trials]) including 3·4 million patients followed up for a mean of 11 months (range 0·7-120). The absolute risk of any cancer with topical calcineurin inhibitor exposure was not different from controls (absolute risk 4·70 per 1000 with topical calcineurin inhibitors vs 4·56 per 1000 without; odds ratio 1·03 [95% credible interval 0·94-1·11]; moderate certainty). For all age groups and using data from observational studies and randomised controlled trials, the use of pimecrolimus (OR 1·05 [95% credible interval 0·94-1·15]) or tacrolimus (0·99 [0·89-1·09]) is likely to have had little to no association with cancer compared with no topical calcineurin inhibitor exposure. For pimecrolimus versus tacrolimus, the finding was similar (0·95 [95% credible interval 0·83-1·07]). Findings were similar in infants, children, and adults, and robust to trial sequential, subgroup, and sensitivity analyses. INTERPRETATION: Among individuals with atopic dermatitis, moderate-certainty evidence shows that topical calcineurin inhibitors do not increase the risk of cancer. These findings support the safe use of topical calcineurin inhibitors in the optimal treatment of patients with atopic dermatitis. FUNDING: American Academy of Allergy, Asthma and Immunology and American College of Allergy, Asthma and Immunology via the Joint Task Force on Practice Parameters.

Interleukin-6 gene promoter-572 C allele may play a role in rate of disease progression in multiple sclerosis.

Multiple sclerosis (MS) is an inflammatory demyelinating disease affecting the central nervous system. Although the exact pathogenesis of MS is unknown, it is generally considered to be an autoimmune disease, with numerous genetic and environmental factors determining disease susceptibility and severity. One important mediator of immune responses and inflammation is interleukin-6 (IL-6). Previously, elevated levels of IL-6 in mononuclear cells in blood and in brain tissue from MS patients have been reported. Various polymorphisms in the promoter region of the IL6 gene have also been linked with IL-6 protein levels. In MS, several small studies have investigated whether two IL6 promoter polymorphisms (-597 G>A and -174 G>C) correlate with MS susceptibility, but with varying results. In the present study, we analyzed these polymorphisms, together with an additional polymorphism (-572 G>C) in 279 healthy controls and 509 patients with MS. We found no significant differences between MS patients and healthy controls for the different -597 or -174 IL6 promoter alleles or genotypes. There was a slight reduction in the percentage of individuals with MS who carried a C allele at position -572, although this was not significant after correction for multiple comparisons. Interestingly, however, the -572 C allele showed a significant correlation with the MS severity score, suggesting a possible role in disease progression.

Complications, Symptoms, Presurgical Predictors in Patients With Chronic Hypoparathyroidism: A Systematic Review.

The complications and symptoms of hypoparathyroidism remain incompletely defined. Measuring serum parathyroid hormone (PTH) and calcium levels early after total thyroidectomy may predict the development of chronic hypoparathyroidism. The study aimed (i) to identify symptoms and complications associated with chronic hypoparathyroidism and determine the prevalence of those symptoms and complications (Part I), and (ii) to examine the utility of early postoperative measurements of PTH and calcium in predicting chronic hypoparathyroidism (Part II). We searched Medline, Medline In-Process, EMBASE, and Cochrane CENTRAL to identify complications and symptoms associated with chronic hypoparathyroidism. We used two predefined criteria (at least three studies reported the complication and symptom and had statistically significantly greater pooled relative estimates). To estimate prevalence, we used the median and interquartile range (IQR) of the studies reporting complications and symptoms. For testing the predictive values of early postoperative measurements of PTH and calcium, we used a bivariate model to perform diagnostic test meta-analysis. In Part I, the 93 eligible studies enrolled a total of 18,973 patients and reported on 170 complications and symptoms. We identified nine most common complications or symptoms probably associated with chronic hypoparathyroidism. The complications or symptoms and the prevalence are as follows: nephrocalcinosis/nephrolithiasis (median prevalence among all studies 15%), renal insufficiency (12%), cataract (17%), seizures (11%), arrhythmia (7%), ischemic heart disease (7%), depression (9%), infection (11%), and all-cause mortality (6%). In Part II, 18 studies with 4325 patients proved eligible. For PTH measurement, regarding the posttest probability, PTH values above 10 pg/mL 12-24 hours postsurgery virtually exclude chronic hypoparathyroidism irrespective of pretest probability (100%). When PTH values are below 10 pg/mL, posttest probabilities range from 3% to 64%. Nine complications and symptoms are probably associated with chronic hypoparathyroidism. A PTH value above a threshold of 10 pg/mL 12-24 hours after total thyroidectomy is a strong predictor that the patients will not develop chronic hypoparathyroidism. Patients with PTH values below the threshold need careful monitoring as some will develop chronic hypoparathyroidism. © 2022 American Society for Bone and Mineral Research (ASBMR).

Parathyroid Hormone Therapy for Managing Chronic Hypoparathyroidism: A Systematic Review and Meta-Analysis.

The efficacy and safety of parathyroid hormone (PTH) therapy for managing long-term hypoparathyroidism is being evaluated in ongoing clinical trials. We undertook a systematic review and meta-analysis of currently available randomized controlled trials to investigate the benefits and harms of PTH therapy and conventional therapy in the management of patients with chronic hypoparathyroidism. To identify eligible studies, published in English, we searched Embase, PubMed, and Cochrane CENTRAL from inception to May 2022. Two reviewers independently extracted data and assessed the risk of bias. We defined patients' important outcomes and used grading of recommendations, assessment, development, and evaluation (GRADE) to provide the structure for quantifying absolute effects and rating the quality of evidence. Seven randomized trials of 12 publications that enrolled a total of 386 patients proved eligible. The follow-up duration ranged from 1 to 36 months. Compared with conventional therapy, PTH therapy probably achieves a small improvement in physical health-related quality of life (mean difference [MD] 3.4, 95% confidence interval [CI] 1.5-5.3, minimally important difference 3.0, moderate certainty). PTH therapy results in more patients reaching 50% or greater reduction in the dose of active vitamin D and calcium (relative risk [RR] = 6.5, 95% CI 2.5-16.4, 385 more per 1000 patients, high certainty). PTH therapy may increase hypercalcemia (RR =2.4, 95% CI 1.2-5.04, low certainty). The findings may support the use of PTH therapy in patients with chronic hypoparathyroidism. Because of limitations of short duration and small sample size, evidence from randomized trials is limited regarding important benefits of PTH therapy compared with conventional therapy. Establishing such benefits will require further studies. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

NMR Studies of G-Quadruplex Structures and G-Quadruplex-Interactive Compounds.

G-quadruplexes are noncanonical, four-stranded nucleic acid secondary structures formed in sequences containing consecutive runs of guanines. These G-quadruplex structures have been found to form in nucleic acid regions of biological significance, including human telomeres, gene promoters, and untranslated regions of mRNA. Thus, they are considered attractive therapeutic targets. Nuclear magnetic resonance (NMR) spectroscopy is a powerful method for understanding the structures of G-quadruplexes and their interactions with small molecules under physiologically relevant conditions. Here, we present the NMR methodology used in our research group for the study of DNA G-quadruplex structures in physiologically relevant solution and their ligand interactions.

Electrophoretic Mobility Shift Assay and Dimethyl Sulfate Footprinting for Characterization of G-Quadruplexes and G-Quadruplex-Protein Complexes.

DNA G-quadruplexes are globular nucleic acid secondary structures which occur throughout the human genome under physiological conditions. There is accumulating evidence supporting G-quadruplex involvement in a number of important aspects of genome functions, including transcription, replication, and genomic stability, and that protein and enzyme recognition of G-quadruplexes may represent a key event to regulate physiological or pathological pathways. Two important techniques to study G-quadruplexes and their protein interactions are the electrophoretic mobility shift assay (EMSA) and dimethyl sulfate (DMS) footprinting assay. EMSA, one of the most sensitive and robust methods for studying the DNA-protein interactions, can be used to determine the binding parameters and relative affinities of a protein for the G-quadruplex. DMS footprinting is a powerful assay for the initial characterization of G-quadruplexes, which can be used to deduce the guanine bases involved in the formation of G-tetrads under physiological salt conditions. DMS footprinting can also reveal important information in G-quadruplex-protein complexes on protein contacts and regional changes in DNA G-quadruplex upon protein binding. In this paper, we will provide a detailed protocol for the EMSA and DMS footprinting assays for characterization of G-quadruplexes and G-quadruplex-protein complexes. Expected outcomes and references to extensions of the method will be further discussed.

Maxillomandibular Rotational Advancement: Airway, Aesthetics, and Angle's Considerations.

Obstructive sleep apnea is a medical syndrome with multifactorial pathophysiology. Surgery can be the primary treatment option when anatomic factors are identified with narrowing at specific or general levels of pharyngeal airway. The surgeries are directed to the etiologic anatomic structure to achieve greatest effectiveness. Body weight, Mallampati scale, and tonsil grade are key evaluations to select effective surgical procedures. Surgical weight reduction, maxillomandibular advancement, and pharyngeal soft tissue surgeries are considered for the patient with obesity, maxillomandibular retrognathism, and tonsillar hypertrophy, respectively. Tailored surgical planning can meet the patients needs for airway, esthetics, and normal Angle's occlusion.

Prevalence of hepatitis C virus infection and the IL28B genotype polymorphism among blood donors and high-risk populations.

INTRODUCTION: To study the prevalence of hepatitis C virus (HCV) infection in blood donor (BD), haemodialysis (HD) and intravenous drug user (IVDU) populations in Singapore and assess the IL28B polymorphism if HCV positive. METHODS: The BD population were healthy volunteers, the HD population were patients who were on haemodialysis for at least six months of follow-up between January 2009 and December 2014. IVDU population was from inmates at halfway houses who consented. RESULTS: Between 2011 and 2014, of 161,658 individuals who underwent screening prior to blood donation, 95 (0.059%) were positive for HCV. Of the 42 sera available, common genotypes (GTs) were GT-3 (47.6%) and GT-1 (31.0%). Of 1,575 HD patients, 2.2% were anti-HCV positive. The HCV GT distribution was HCV GT-1 (32.4%), HCV GT-3 (20.5%) and GT-6 (8.8%). 83 halfway house inmates were screened. Of the 47 IVDUs, 36.2% were anti-HCV positive with predominant GT-3 (%). IL28B polymorphism was noted to be CC predominantly 85.3%. CONCLUSION: Prevalence of HCV infection has decreased in both the BD and HD populations. However, it remains high in the IVDU population. GT-1 remains the most common in the HD population; however, GT-3 infection is now more common among the BD population in Singapore. IL28B - CC is the predominant variant among the HCV-infected individuals in Singapore.